kv string to map
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console.log("Hello World!");
function toMap(str){
var ret = {}, len = 0;
if(str === undefined || (len = str.length) === 0){
return ret;
}
if(getType(str[0]) != 1) throw Error("字符串应以字母开头");
var k = "",v = "";
var hasK = false,hasV = false;
for(var i=0; i<len; i++){
var ch = str.charAt(i),type = getType(ch);
if(type === 1){//letter
if(!hasK) hasK = true;
reset();
k += ch;
}else if(type === 2){
if(!hasV) hasV = true;
v += ch;
}else throw Error("非法字符")
}
if(!hasK || !hasV) throw Error("缺少key或value");
reset();
// reset related state if find both k and v;
function reset(cb){
if(hasK && hasV){
ret[k] = v;
hasK = false;
hasV = false;
k = "";
v = "";
}
}
function getType(ch){
if('a' <= ch && ch <= 'z') return 1;
if('0' <= ch && ch <= '9') return 2;
return 0;
}
return ret;
}
// test
console.time("ElapsedTime");
console.log(toMap("abcd1sdfs2xyz3"));
console.timeEnd("ElapsedTime");
// 非字母开头将会报错
// console.time("ElapsedTime");
// console.log(toMap("111abcd1sdfs2xyz3"));
// console.timeEnd("ElapsedTime");
JavaScript
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